Search Publications
Deep XMM survey of M33
Pietsch, W.; Haberl, F.; Ehle, M. +2 more
In an XMM raster observation of the bright local group spiral galaxy M33 we study the population of X-ray sources (X-ray binaries, supernova remnants, super-shells) down to a 0.5-10 keV luminosity of \oergs{35} - more than a factor of 10 deeper than earlier ROSAT observations. EPIC spectra and hardness ratios are used to distinguish between differ…
Toward a self-consistent treatment of the cyclotron wave heating and acceleration of the solar wind plasma
Laitinen, T.; Fichtner, H.; Vainio, R.
We have developed a steady state two-fluid description of the radial solar wind expansion close to the coronal base. The model is formulated self-consistently with respect to the radial evolution of turbulence by supplementing the moment equations of the plasma with an equation describing the radial evolution of the Alfvén wave power as originally…
Far-Ultraviolet Observations of the Circumstellar Gas in the 2 Andromedae System
Neff, James E.; Cheng, K. -P.
The A5 star β Pictoris is a possible young planetary system and has the best-studied circumstellar disk. Our visible and ultraviolet observations of 2 Andromedae indicated that this A3 star has β Pictoris-like gas infall. We present the far-ultraviolet spectrum (905-1195 Å) of 2 And we obtained with the NASA-CNES-CSA Far Ultraviolet Spectroscopic …
Magnetic clouds with east/west orientated axes observed by Ulysses during solar cycle 23
Forsyth, R. J.; Rees, A.
The second Ulysses orbit of the Sun has provided a unique opportunity for the study of the interplanetary manifestation of coronal mass ejections (ICMEs) over a wide range of heliographic latitudes. The Ulysses dataset between July 1995 and mid April 2003 has been surveyed for magnetic clouds (MCs), a subset of ICMEs. As a result of the rising sol…
Abundances of the planetary nebula Hu 1-2
Pottasch, S. R.; Beintema, D. A.; Feibelman, W. A. +4 more
The ISO and IUE spectra of the ``elliptical'' nebula
An extension of Herschel's method for dense and extensive catalogues. Application to the determination of solar motion
Bongiovanni, A.; Vieira, K.; Abad, C. +2 more
We present a way of handling and interpreting stellar proper motions, in which the idea of substituting them by great circles, proposed by Herschel in 1783, allows us to take the entire celestial sphere as a field of application, making possible the study of dense and extensive stellar zones. A suitable mathematical processing of data together wit…
Castor A and Castor B resolved in a simultaneous Chandra and XMM-Newton observation
Burwitz, V.; Stelzer, B.
We present a simultaneous Chandra and XMM-Newton observation of the Castor sextett, focusing on Castor A and Castor B, two spectroscopic binaries with early-type primaries. Our study represents the first unambiguous X-ray detection of all three visual components in the Castor sextett making use of the unprecedented spatial resolution of Chandra. O…
XMM-Newton view of the Hubble Deep Field-North and Groth-Westphal strip regions
Griffiths, R. E.; Miyaji, T.; Lumb, D. +2 more
We report the progress on our analysis of two deep XMM observations in the areas of Hubble Deep Field-North and the Groth-Westphal Strip field. We present the source detection method, Monte-Carlo simulation on source detection, and our preliminary Log N - Log S relations. Comparing these two fields and other fields in literature, we find up to ∼ 3…
First results of IBIS/ISGRI Cygnus X-3 monitoring during INTEGRAL PV phase
Goldoni, P.; Bonnet-Bidaud, J. M.; Falanga, M. +1 more
We report on preliminary results of IBIS/ISGRI serendipitous observations of Cygnus X-3 in the 15-100 keV energy range during the INTEGRAL Performance and Verification phase. This peculiar microquasar was inside IBIS/ISGRI field of view at a ~ 9deg distance from the pointing direction during Cygnus X-1 staring observations in November a…
The Discovery of Globular Clusters in the Protospiral Galaxy NGC 2915: Implications for Hierarchical Galaxy Evolution
Ford, H. C.; Infante, L.; Zheng, W. +30 more
We have discovered three globular clusters beyond the Holmberg radius in Hubble Space Telescope Advanced Camera for Surveys images of the gas-rich dark matter-dominated blue compact dwarf galaxy NGC 2915. The clusters, all of which start to resolve into stars, have MV606=-8.9 to -9.8 mag, significantly brighter than the peak of the lumi…